Hi and welcome,

To see whose chip you have you need to open up the ECU,and hopefully it will have a sticker on the top identifying it, even if you have a receipt this could well have been changed since unless it's a recent receipt I guess, for a T34 to be fitted it is most likely to be stage 3 (If you look at the injectors they are most likely to be green or grey, or could even be the equivalent Siemens 55LB.

Rolling road is a good idea as it allows you to see how it's performing and highlight faults as well, all in safe confines.

No point in boost controller the standard Amal valve is perfectly ok, you may find it's this that is causing your low boost, it should click when the ignition is switched on. 15PSI is nothing that is stage 1 boost, you should have around 20+ generally speaking. There is a simple mod you can do known as "Two stage boost" which involves fitting a switch.

Martin