ATC SCM50ASL Pro vs ATC SCM 50ASLT

Jeez, if SCM100 pros are still cheaper than SC50Ts, you could get the SCM50 pros and pay a carpenter to build an identical dimensioned cabinet with the same roundovers and a luxury veneer!

Why would you do that?
Sounds like a recipe to write off investment in a genuine ATC speaker system.

Personally I don't mind the look of the ATC Pro speakers, though the domestic tower versions have their advantages.
Better WAF for one, though ATC towers don't conform to the slim aesthetic that seems to be in vogue these days.
I have SCM100 towers and like not having to mess with stands (I use my towers with Townshend podiums).
The grill covers also keep the expensive drivers out of sight to any over curious children (and adults!).  
Domestic versions have the squared off protruding baffle designed for use with the grill cover that incorporates the rounded frame. Many people use the domestic versions without the grill covers, and they are often demoed that way, but I prefer the sound in my system with grills fitted. 
If you like to ogle the drivers then perhaps consider the Pro version which are provided without grills and have the rounded off frame around the front baffle.

Oh come on it’s just a cabinet; there’s no voodoo to the ATC cabs - I’m just saying if they find the Pros ugly (I don’t - I got the 20 pros rather than the 19s, though yeah, they're not lookers), they could swap all the internals for a beautiful new cabinet. Replicate the bracing, lining, stuffing, vent, amp cutout, done. Of course, the 100s have more bass, but they’re bigger, more expensive, and the Pros will look as ugly to them as the 50 Pros.

Oh come on it’s just a cabinet; there’s no voodoo to the ATC cabs

No voodoo for sure, since that isn't the ATC way.
However any deviation from how ATC does its cabinets will result in different sound - why reinvent the wheel with the possible compromises?
If saving money and 'shiny' cabinet is required I wouldn't cannibalise a genuine ATC to do it, just saying.
Get the Pros or the Domestic version or purchase/build something else if they aren't to ones taste or budget.    

I do not find the the ATC PROs ugly, I’ve owned Merlin monitors in black rough and it was fine.  My original post simply asked for confirmation and/or insight into my understanding of the identical nature and performance of the two ATC products.

No veneering will take place.  Thank you.

There is a difference between the pro model and the domestic model. While both of them are 50L cabinets, typically ATC suggests the monitor model if the room dimensions are relatively small. The floorstand version sounds a bit larger/bloomier hence it can overwhelm more easily in less than 250sqft room. My guess is it is due to the way bass builds up when speakers are on the floor. The monitor version when lifted on stands sounds a bit more compact and may be a shade dryer. Recently my cousin was in a similar dillema while deciding between active studio SCM100 vs active Floorstanding SCM 100. We asked it to ATC and their suggestion is as above. My cousin picked the studio version finally since room was just about adequate in size.