For the old adjustable style FP's

If you add a lift kit without shortening the BAS or adding a spacer between the BAS and the bolt handle, You are compressing the spring even more. So that needs to be addressed.
Adding a set screw to hold the cocking piece pin can help address the cocking piece pin tilt/alignment. 1/4 - 28 is correct I think.
Polishing the firing pin spring ends(inside and outside) and even sanding down .005 on the OD of the spring will help. Use a drill and sandpapper not a grinder, unless you are a stud with a good setup to keep the diameter even. If you polish or sand always use something fine to finish. A 16 rms finish would be the minimum for me.
Use a small amount of good bolt lube/grease on the backs of the lugs.
Using a createx bit, polish the cocking ramp and edges. If the bolt close feels "notchy", then send it to Fred. He will T&T it if he still performs that work. Do not radius the edges of your bolt head ever, you have a timing issue not a sharp edge issue.
If your bolt gabs on close during the throw try applying force to the opposite of the bolt handle. Also using a flat hone you can remove some roughness from the bolt head raceway.

I'm am not real good with words so I hope some of these tips help.