Picked up a few old E and G reels, was wondering if anyone has any knowledge on different/upgraded main gear and pinions that will fit from newer shimano reels. Also where I can get new side plates for the E series.

Side plates are still available from shimano as far as I know. I expect the changes in frame size and addition of the x ship bearings exclude gear swaps from Current models someone at shimano might be willing to confirm.  There was nothing wrong with the gears they came with though. Carbontex drags, super tuned and freshening spool bearings if needed and they run with anything made currently. 

I had the E and sold it but still own the G.  Both reels are great when properly taken care of.  Like DVT said above, about the best thing you can do is supertune it and update the bearings.  I have done both on the G I have.  The supertune made it a little smother but not much.  It was pretty smooth to begin with.  I did upgrade the bearings to ABEC 5 Boca ceramics and it did cast further.  I also tried the ABEC 7's and didn't see where they were an upgrade from the 5's in terms of smoothness or casting.  If I had to do it all over again, I would have ordered the stock bearings that go in the Calais/Antares from Shimano.  They are the same size and this would have been a major improvement over the stock. I also feel that these bearings are as good or even better than the "upgraded" type bearings out there.  They are also cheaper, $14 each.

I have three 50E's and three 200E7's and they fish today the same as out of the box years ago.  All of them are still stock and I just keep them clean and lubed properly.   Really nice dependable  reels.

This is all awesome info guys! The reason for the gear swap was because I have yet to open up the E and just want to be ready for when I do. The side plates have some rash but nothing major, I couldn't find the parts list on shimanos website but I'll give them a call on monday and find out, as for the bearings I'm going to look into that, I've heard good things about those OEM bearings.

About 8 years ago, I bought a 301E curado, and 2 201E curado's. Swapped out the drags for carbon drags, and kept them oiled and greased, never had a issue. Wound up selling them, and to this day, I wish I had them back. Great reels imho.

1 hour ago, DomQ said:

This is all awesome info guys! The reason for the gear swap was because I have yet to open up the E and just want to be ready for when I do. The side plates have some rash but nothing major, I couldn't find the parts list on shimanos website but I'll give them a call on monday and find out, as for the bearings I'm going to look into that, I've heard good things about those OEM bearings.

Shimano started redoing the website and never completed it. Lots of schematics are missing. 

24 minutes ago, Delaware Valley Tackle said:

Shimano started redoing the website and never completed it. Lots of schematics are missing. 

Thank you! That's a relief 

Love the E's

You can also get parts on e-replacement parts. Some of the odd parts for E series are N/A but most are there. 

Nice reels!
 

You may know but last I looked Shimano didnt have the E series curados listed for parts but had the Chronarch E’s up- which are essentially the same reels beyond cosmetics. 
 

Worst case going forward parts are also often suprisingly available for older jdm variations