If I remember correctly this is a US spec car you have and you were intending upgrading the engine. What have you done, or what are you intending to do.
Efi is certainly a consideration, if your happy with that sort of approach, however personally for me if it’s not Pi then carbs would be my choice. If you have no previous experience with Weber’s then it’s important to appreciate what your taking on.I’ve been using them since the mid 70s, firstly on a Lotus Cortina then on my Tr6 and I’m still learning. I would say only go this route if your prepared to take on the extra learning and enjoy it
Having said all that, once the Weber’s are set up properly they are very reliable and car be reasonably economical, particularly when touring. Last year three of us covered 2500miles across France and Spain, my car and two PIs, I used the least fuel. However give the car a bit of welly and your down in the mid teens MPG.
I would recommend you watch this series of videos .This guy explains things well and will answer a lot of your questions.