I worked for British Leyland in the early 80s..had 4 TR7s and a TR8I admit, since I had such a horrid experience with my '80 TR7 back in high school, I am so tempted to find one and build it correctly. Even now I take it very personally how often my ass was kicked by that thing.
Naturally aspirated lightweight modern V6 (original 4 pot was cast iron and heavier than most modern sixes)
Modern gearbox
InfinityBox wiring loom and modern electrical systems and interior lighting
Modern-ish rear suspension
Re-design the grotesque US spec bumpers
Modern HVAC