This might be interesting for some of you:
I have been shooting a Target 3+ with the 95# spring for about a year, but recently became more and more aware of the fact I really could use a stiffer spring to pre-load the trigger more confidently.
Alas, the 135# spring was all but impossible to fire. So I E-mailed Carter to ask whether there was an in-between weight spring available. Mr Forrest Carter replied with a surprisingly simple solution: Cut off 1/16" of the 135# spring.
I used a dremel to carefully cut a bit off, and it worked out exacty the way I wanted.
I just thought I'd share this for anyone with the same problem!