Insurance is reasonable for an old guy like me,38.At least in my area CT is prolly higher.For you it would be pretty much the same as any high performance car.
LC2 's can be reliable,there are lots of people using them for daily drivers.Some parts are getting $$ and hard to find.
GNs and TTypes have the same drive train.TTypes came in different colors and GNs have a unique interior only found in GNs and GNXs.
The 200-4r in a GN/TType is strong for a 200.It's not the same as a 200 in a Monte.If you need a rebuild don't trust just any shop to rebuild it.Go see Jack Cotton in Agawam MA.He'll hook you up with an Eric Shertz tranny.
I'd have to agree with you,from looking in your Autotrader link.TRs cost too much in your area.You can't get close to that much $$ for them around here.There's an 87 GN around here w/150k miles runs great,new paint,nice interior,asking $5300.If I wasn't building a garage right now I'd prolly own it.
A bit of advise if you find a TR your interested in have a knowledgable TR guy go with you look at the car and see how it runs.