So then I removed the scope, rings and finally the base. The four screws were decent tight and I they were screeching as I loosened them, and there's tons of oil beneath...
I wiped off the oil completely. Then installing only the 2 front screws tightened them a bit, I checked for slop on the rear of the rail, but I can only find very very minimal slop/gap. But I was telling myself this aluminum rail may have already bent a bit since it was already installed at the factory. I didn't consider bedding with JB weld for minimal gap considering my rings already aligned from the previous install.
But I would really be interested on how much a new rail leave a gap for bedding. So I degreased the holes, screws. Put a very thin film of grease on top of receiver and then installed the 4 bolts with blue loctite.
I noticed as well that the first screw hole towards the muzzle, you would see the barrel threads (a bit flattened by the screw) in the chamber:
Since the 4 bolts are all of the same lengths, I was considering shortening 1 screw but was very hesitant as I may not be able to start threading it back. So I just left it alone. But I hope I didn't mess-up with threads (barrel & base screw) upon torqueing to 20 in-lb. I will only be able to see that if I am to change the base/rail or when they loosen up. But everything went well all 4 bolts torqued to specs.

You can clearly see here that the bolt on the right has more gap after torqueing than the left.
Then I installed the rings checked for alignment and lapped them a bit more ~ 60% and seated the scope.
Then about removing the stock, I read savage's manual and recommends to remove the screw at the front of magwell and the one beneath the bolt release. But I've seen youtube vids also removing the 3rd screw behind the trigger guard. So do all 3 has to be loosened? That's why I think I will shoot this first with the factory-installed stock.
Is it very complicated reinstalling the stock back as one has to torque the bolts in a particular order with 5 in.-lb increments until the full torque specs? Need inputs on this.