With constructive criticism in mind, the switch from twin carbs to single carbs has a lot against it. However, if you must do it, say, just for the fun of it, spend all your hard earned cash on modifying your head and be prepared to be disappointed in the results.
The parallel port head was a move that Triumph SHOULD have made many years prior. Tuners in the fifties and sixties spend a lot of time and money correcting the inlet port shapes to get power and efficiency from this motor. Triumph apparently never looked at their results.
Re-angling the inlet ports was one of the things they did to help correct the tendency for these motors to detonate or experience pre-igntion.
What you have with the parallel inlet head is the final product of Triumph finally bending to winds of change and now you want to mess that up.
Go figure.
For the fun of it, Sure, have at it.
For practical reasons. Money is better spent doing other things to your bike.

1974 Commando
1985 Honda Nighthawk 650
1957 Thunderbird/T110 "Black Tiger"
Antique Fans: Loads of Emersons (Two six wingers) plus gyros and orbiters.