So, my lever gun project is on it's way. I'll get the gun tomorrow. My smith will swap out the barrel for me. I may send it away for a trigger job.
I want to do everything I can to make this rifle function as well as it possibly can. I always err on the side of caution and I don't mind doing the work. The reason my XD has such great trigger is because I was willing to take it apart and polish parts then put back together and test it, over and over and over.
I'm perfectly willing to pay some money to learn what I want to.

Suggestions?

The BLR has straight knurled pins in the reciver.
If you install and remove them a lot they will likely chew up the holes in the receiver.

You might look at Hooke's Law and learn how to calculate spring loads for the trigger return spring. You can measure the trigger pull without the hammer being cocked and determine the contribution of the return spring vs the total load with the hammer cocked.
Reduction of the return spring can be done simply by substituting a similar spring with a lower spring constant.
The rest of the trigger is more tedious and you might thing about making a tooling block with holes in it for the hammer and trigger pins. This will permit you to check the parts outside of the receiver where you can see the contact surfaces.

If there is any doubt have a BLR specialist tune it and let me know who he is.

Those are some great suggestions. The tooling block is probably a normal kind of thing for a full time gunsmith, but it is a new thing to me. Very cool.

The differences between the tooling block and the action itself can cause variations in the contact points. The best way if you can't duplicate the dimensions of the action very closely is to use machinist blue to find out where the contact points are and then stone them until the contact is at 90 degrees and full surface. Then you can play with engagement while making sure that there is enough for safe operation and little enough for a crisp pull without noticeable creep.
Installing limit screws for engagement and over-travel will help if there is room.

I'm going to need some more detailed info before I start taking anything apart.
When I started working on my cz-75 I got a video and watched that first. In the video they talked about a "slave pin" and explained how to use it. I don't think it is possible to get the cz-75 put back together without the use of one of those pins. I don't want to get into the same kind of thing with the BLR.
Somebody else already described giving their BLR to a smith and getting it back in pieces because the smith couldn't get it back together.