Am I gonna have problems using wilson parts to build..internal parts that is like the hammer,trigger,springs?
Remember, you're dealing with Non-Colt, Non-GI parts.
The Colt's and old USGI guns were built to Colt standards, and these specs were slavishly followed.
You either met the specs, or you weren't a GI supplier, period.
Plus all parts were made from forged, milled parts, NO castings.
Today, all makers follow whatever specs and standards they want. Second, you're dealing with a cast frame, and probably cast parts.
Most cast frames and parts WILL vary in at least some areas. Pin holes may not be square or may be mis-located, rails may be high or low or misaligned, etc.
What you're dealing with is a mix of parts from different suppliers and these parts WILL have at least some variation.
The problem is going to be one where something doesn't fit or function properly. Since you won't know which part or parts are at fault, it can be tough to diagnose the actual problem and figure out what needs to be done.
In other words, there's no such thing as true "drop-in" parts, and all parts may need at least some fitting.
How much or how little trouble you'll have is just luck of the draw.
The problem is compounded when you're trying to build a non-standard gun. In other words, you're trying to use "Match" or custom feature parts like Match sears and hammers, non-standard grip safeties, etc.
These parts almost always need hand fitting, and often don't "work right" without some diagnosing of the problem.
This is worst in a gun that wasn't functioning properly to start with. (A new gun).
With a functioning gun, you pretty well know the problem is with the new part, not the working parts.
For this reason, I usually recommend building a GI-spec "loose" gun. AFTER you get a properly working, properly functioning gun, THEN start installing the non-standard parts and features.
I have built a gun using a frame and slide from Essex.
I used Wilson parts and did not have any problems with fitment. This was about 5 years ago. I felt that the quality of the frame and slide was excellent.
The pin kit, hammer, sear, disconnector, barrel and every other part went in fine.
I cannot speak to the quality of them today.