Hey guys, I've been lurking on this forum for a while, but this is the first time I've posted, I'm hoping all of your expertise might be able to help me.

I am pretty new to cycling and working on bikes, but I've always been pretty mechanically inclined and have had a lot of success with all the others repairs and tune-ups I've done so far so decided to try something a bit more involved.

I have a Redline Conquest Pro that I got second hand, it's my first road bike (cyclocross) and it came with an FSA Gossamer crank and FSA Megaexo bottom bracket. I think the BB was original and it finally bit the dust recently. I decided to replace it with a Shimano external bottom bracket as I've heard they have a bit more longevity and I know they work with FSA cranks.

Anyway, the drive side FSA bearing cup came out just fine, however, I had to apply a ton of force to remove the NDS bearing cup and when I finally managed to get it out nearly all of the threads on the FSA cup were stripped and the threaded surface was nearly smooth. I also pulled a bunch of aluminum strands/shavings out of the BB shell which were presumably the threads on the cup.

I took a look at the BB shell threads and they all looked fine, there was no obvious damage so I decided to go ahead and try to install the Shimano cups, again no problem with the drive side, but the NDS cup required more force (probably a sign I should have stopped) but much less than it took to remove the FSA cup. After I had it screwed in all the way, I backed it out again to see if the threads were damaged (yeah, probably another bad idea), and the threads definitely were damaged/stripped, a bunch of the thread surface was pretty smooth again, but some of the threads near the beginning and end survived and the cup seems to still be really tight in the shell.

Is it ok to ride it like this, and if not what can I do to salvage the threads and the frame, like I said I didn't see any obvious damage to the shell threads, but then again I'm pretty new to this.

Thanks for helping a new guy to this forum and this sport
-TK