The TF is among the rarest of the MGs. I plan to add a MGA Twincam
soon.

I guess you need to add the bigger engine because of your weight. That
TF can't even get out of it's own way with a 16 year old girl driving
who is a size double 0. I guess that's why every time I see one of
those things on the road it's being driven by some little skinny fart
with a goatee. While your replacing the engine you may want to do the
springs and shocks. The exhaust system is probably hitting the road
with you in the car. Why not just unload the little anemic POS and get
a used Viper?