Classic & Vintage - Rampar guinea pig

I am trying to learn to work on my bikes instead of taking them to the bike shop for every little thing. Just too much hassle. My mom's old Rampar (1980ish) has been elected to be the guinea pig.

Servicing the bottom bracket is the first job. I managed to get the cranks and the lock ring off, but then ran into trouble. I had purchased Parks's green pin spanner before I ever started, hoping it would be the right one. Of course it isn't. Instead of having two holes to fit the pin spanner in, the adjustable cup has two slots. They are a little under 1/4" tall and run the width of the ring.

Does anybody know what tool I need? I couldn't find a close up picture of the other Park pin spanners (the red and yellow) to see if one of them was flat as opposed to a round pin. I probably could knock it loose with a screwdriver, but I hate to booger stuff up like that. The crank has RS (or maybe SR) stamped on it like that is the brand. I haven't heard of that in my limited experience, but, hey, it's a low end bike.

I just know one of you guys who do a lot of flipping has run across this before:p.

Thanks

SR = Sakae Ringyo, an innumerable quantity of 80's bikes were built with SR cranks, stems and seatposts. The products range from awful steel-ringed swaged stuff to really nice, light, forged cranksets.

Have you tried just turning the cup with your fingers? If the lockring is already off it should move pretty easily, unless you're about to have a bad day. Try putting a screwdriver in the notch like you already mentioned but just tap it with the palm of your hand instead of a hammer. It may just have a little dried grease in ye olde threads.

Thanks for the info. I will try a little gentle persuasion. +1 on the old grease. What I have seen so far has been the consistency of taffy. The bike is in good shape, less that 100 miles on it, but it has been stored for the last 20 years. I know for a fact the BB hasn't been opened since the day it came off the production line.