That’s really neat. I also like the SA V10 Ultra. Here is some information on them and you may already know about them. I’d love to have one and wish they would make them again. There was a forged frame and a cast frame, easy way to tell is the cast frame is the plunger tube is part of the frame, the forged frame the plunger tube is a separate piece riveted on. Another way is the position of the serial number, below the slide stop forged(engraved) and in front of the slide stop pin is cast(roll stamped). The forged frame was too expensive to produce so they went to casting it. Serial number prefix of HC is forged and WW can be forged or cast. I think there is one other prefix that exists that was on the forged frame also. The forged frame can use SV magazines with a modified mag catch, the SV ITS trigger system will fit also. The old King's ambi worked great but it is out of production, any of the right side ambi that is retained by the hammer pin will work. The front strap is squared in shape as opposed to Para's they are more rounded. The serrations on the front are 20 lpi so most checkering is done in that size. There is enough material to remove the 20 lpi serrations and cut 25 lpi checkering and round the corners more.
Given the choice between forged, cast or a Para frame I will always go with the forged frame.