do you frequently see old cars in their lot? are they actively being worked on and not just sitting for months at a time? is there mopars? do any of the mechanics own old cars, especially mopars?
the suspension work might be a specialist type thing. a lot of shops won't touch that unless they're intimately familiar with mopars. the leaky transmission, if it's something simple like a pan gasket or shifter seal, they should be able to tackle. any more than that you might want to hunt down somebody with more granular expertise.
get a heat check by looking at their yelp/google reviews and any online presence they might have. then talk to customers. see if you can find one that wasn't all rainbows and unicorns about their experience and get a bead on what went wrong, with the how and the why and what the shop did to make right by the customer.
word of mouth rec is always the best way to track somebody down to do the work. and it might just be some dude that has a big garage at home and does one or two cars a month as side work.