Amp blowing fuses

I have a pair of quicksilver kt-88 monos and one is blowing 3A slo-blo fuses instantly on powerup. I have swapped all the tubes from its mate and looked at the chassis wiring which is discrete, point to point. It looks clean with no hints of overheating or trouble. I've thought about trying a 4A fuse but wanted to get opinions as maybe one of you have had a similar problem... thanks for any help, opinions etc...
From a different standpoint, I had something similar happen with my 2 new VAC Statement monoblocks. Turned out that all fuses aren't necessarily the same. There is a greatly increased amount of current when an amp first turns on and if the fuse is not designed to accept this,it will blow most every time, regardless of its amperage rating. That's what happened to me when I got local Radio Shack slo blo fuses, as compared to the slo blo fuses VAC sent me.

My point is that before you go to any more trouble, just have Quicksilver send you some spare fuses for your amp. They will know which ones to send if you describe your situation. That would be the first thing I would have done. The other suggestions above are also helpful, but the easiest fix to try would probably be what I am suggesting. Good luck.
I repeat, you could have a bad rectifier in the filament supply.....
I agree with Hifigeek1, and a much higher probability than a transformer shorting.

To save some money, do you know anyone with basic electronics knowledge that owns a multimeter and soldering iron? They could measure the bridge rectifier, transformer, and anything else for shorting. Read the part numbers off any failed component, and order a replacement from many sources, excluding the transformer which would be available from the mfr.

Orrr, take it in for repair. Shouldn't be too costly unless a transformer.

I have a multimeter and a soldering iron but am a bit intimidated by a tube power amp...
Besides unplugging the amp, just make sure to bleed off all capacitors, if they are not already drained off with resistors across the +- posts/leads . Use an insulated handle screwdriver, or insulated wire with both ends pre-stripped 1/4", to short all capacitor leads just to be safe. That *will* resolve any "stored" shock potential.

I assume you know how to measure a bridge rectifier or discrete diodes, etc. If not, report back or google it. Very simple.