I’m putting 40IDF’s on my buggy and am wondering what fuel pump to use and what pressure to run it at. The engine is 1641cc not to heavily worked, just cleaned up and balanced. Any one running a good set up?

I would recomend a carter fuel pump and a regulator set at about 4 psi or less.
This is just a general answer based on what I have run with webbers on other cars. It all depends too on what needle and seat you are using, I have used a 3mm with great success but thats on a 48 IDA downdraft. I wouldn't expect it to be too different on other set ups.
But, if you have not done much work to the motor then the stock fuel pump may work just fine as you wont be using any more fuel than before but now you will have 2 fuel bowls instead of just 1.
I think you will be ok with a good stock pump.

Cheers Tony

Unless you want to get carried away - just run the stock mechanical.

Spen your money on a good fuel regulator.