It's not hard.
Get a disassembly manual, follow the procedure, then, replace the OM internals once you remove the transfer bar parts.
Gun Digest printed some EXCELLENT books with step-by-step, pictured instructions on disassembly. The books are broken down into types of firearms. You'd want the "Revolvers" book.
But I think there are many other manuals out there as well on how to disassemble a Ruger SA as well. It's really NOT very hard at all.
Biggest piece of advice; Get PROPERLY fitting screwdrivers first.
Too many buggered up screw head out there already!
When I do one,, I lay out the parts on my bench in the order in which they were removed. And I do so in a manner that I can easily look at them & see where they go & how they go.
BTW; Old Models are easier than the New Models a bit.
Also; Once an OM has been factory converted to the transfer bar system,, there are NO modifications to the internals. Only a mark on the bottom of the main frame, hidden once the gun is assembled. It's a lawyer thing. If you re-convert one, that they converted, and someone gets hurt,, they can use the mark as a way of releasing them (Ruger) from liability.
PS; I was typing as Dan was responding. Yes, sometimes there have been people who did have issues doing this,, but more often when trying to add parts not originally fitted to the gun.