Dahlquist crossover upgrade from Regnar?

Has anyone upgraded their old Dahlquist speakers with the crossover kit available from Regnar? I have a pair of M-905s which I still love, but I’m curious to know if the upgrade kit makes an appreciable difference in the sound quality?

Also, how tricky is the installation? Can’t be too bad (ha, famous last words…), but if there are any tips or tricks you can share, please send them my way.

If anyone has experience with this I’ll appreciate hearing your thoughts. Thanks in advance!
I ordered the upgrade kit from Regnar for a pair of DQM-9 speakers that I bought from the original owner. I don't see any problem with doing it, and there is definately an overall improvement in clarity, detail and bass power. That said, if I had to do it again I would have bought everything that I needed from Sonic Craft. I say this because Jeff there has a lot of knowlege about crossovers, and besides that, you can get caps that are as good or better for the same price or less. Also, realize that the Regnar upgrade does not include wire, resistors or inductors. Now, it isn't a must to change these things, especially the inductors, but if you are going to all of the trouble, why not do it? It makes a difference too. It is nOt that hard to do, especially if you can solder. The DQM-9 was more difficulT becuse the crossover was at the base of the enclosure and the sidewall; so there was a real spaghetti mess of wires. It is a must to take photos of everything as you take it apart. That makes it easier. In conclusion, if you like the speakers, do it. You will be glad you did.
Thanks for the info Roxy54, much appreciated. I took a look at the crossover board last night (and took photos), looks very simple and well within my tinkering/soldering capabilities, so I will definitely go the DIY route. Planning to call your guy Jeff at Sonic Craft, looks like they have a lot of choices for the components.

Main obstacle I have now is I don't know the specs of the capacitors. I'm going to email Regnar, hopefully if I ask really nicely they will share this info with me even though I'm not planning to buy their kit :/ So, I know this is a crazy longshot -- but if anyone has detailed info on the M905 crossover circuit, please share...I've googled the #&$% out of it and no luck.

Thanks again!
I think that if you look at the individual caps and resistors they will have the values printed on them. Mine did. While I was in there, I also put some scraps of sorbothane sheet that I had hanging around between the crossover board and the speaker wall to isolate it from vibrations.
Well, the resistors are clearly marked, no problem there. But looking at the caps is a fifty-fifty proposition...

One of them says "10K 100V" which I think makes it a pretty unusual spec (just based on what's available at Sonic Craft, there are not too many product choices for this capacitance).

But the other one just says "Dahlquist 1060 - Mexico"...Which is pretty cryptic. So if anyone knows what the actual capacitance of that little bugger is, please fess up!

The inductor has no markings at all, so that's a mystery too.

OK, just in case anyone is following this, or at least for the sake of future generations, the mystery of the unlabeled capacitor has been solved. I called Regnar and asked about the M905 cap specs...

1. Low-freq cap is 10,000 micro Farads (as labelled)
2. Hi-freq Mystery Cap is "5,000 to 5,500" micro Farads (allowing for 10% tolerance)

I also asked what brand caps ship with Regar's M905 upgrade kit. He said they're made by a European company called SAS. Doesn't ring a bell for me, but then I'm not very knowledgable about this kind of stuff. Haven't decided yet what caps I'll use yet, I'm planning to call Sonic Craft this week and ask for some info & advice.
Just seeing your post.  I just got a set of m905s and would like to recap.  Did you find out what the proper replacement is?  Thanks,
Call Jeff at Sonic Craft and if necessary email him a picture. He will guide you.