I am struggling to think of mods i can do to my 1989 Tp.
I have already done:
Sound system inc. Door speakers and subs
Aftermarket steering wheel
TP Elite Digital Cluster
Velour interior swap.

Anyone got suggestion to improve my Tp

Put on a higher flowing rear muffler. Best mod I've ever done.

Elante Kit :)
And some nice 17" wheels :)

tr cam and rollerrockers lumpy sigma cam with solid lifters
tn/m centre console imo look better then the tp console

Extractors to go with the hi-flow rear muffler.
Cheap as chips and made a real difference to my manual TM back in 1987.

tr cam

Does the Tr cam make any difference to performance without a Tr ECU and injectors and rail??

from what i've read on here they are better plus they have better duration lube's and roller rocker
i cant say what there like in a cam swap
every one iv'e done has been part of a full motor re build full tr gear

Elante Kit :)
And some nice 17" wheels :)

I've been hunting for an elante kit. Can't seen to find one.

as for mags, Its tricky to find a nice set of 16+ inch mags that are 4 stud.

is the TR roller rocker swap difficult

is the TR roller rocker swap difficult
Just unbolt and swap them over very easy. You can swap the cam as well. The Tr cam has the valves open about 2 to 3 degrees longer but not sure if it makes much difference in the Tp.
The Tr/Ts have had their ECU remapped to take advantage of that and also have different injectors and slightly higher fuel delivery pressure to get a few extra kilowatts. Vee