I’m working on the same thing I’m planing to use Sorens modified rom https://pinside.com/pinball/forum/topic/new-theatre-of-magic-software-mod-version-2#post-5070060
It supports the tiger saw mod on solenoid driver nr 19 and some other fixes like ball save if hocus pocus magnets misses the ball. There’s also a patched version so you wouldnt need the u22 chip. All you need is to connect the motor thru an EMI filter, very important. I just created a pcb based on williams common motor EMI filter. I made 10 of them if someone needs one. They were all out of stock everywhere I live in sweden
I’m gonna do some measures and tests first, but for what I understand it is just to connect on J116-2 and J126-3.
Please keep us posted and I’ll do the same
Good luck!

//Dennis

Just finished my tiger saw mod

I can post more images if someone's interested!

Build cost:
DC Motor $0 (found it in the trash at work. Could be any 12v dc motor)
Gold mirror saw blade $20 on ebay (optional, for the fancy look)
EMI motor filter about $2 self made ($15 for a new) (actually I made 10 of then and gave some away in exchange for money)
PWM to control motor speed $3 from Wish (optional, if you want the blade to move slower)
Some scrap nuts, bolts and wires.
Total $25 (due the the EMI filters I actually made some money on the build )

If you use the original saw blade and only buy the EMI filer you could get it done for $15. DC motors you could easily find if you look in electronics recycle bins somewhere.
I chose between 3 different motors that I found. Ended up with the smallest. It was from an old printer.

They have it in stock on free-play.se https://www.free-play.se/en/playfield-parts/playfield-plastics/plastic-sets/theatre-of-magic-complete-plastic-set.html