Bottom end bearings are the same as the N/A, city E, Pro-T etc... You can buy these over the counter, ACL supply them.
Rings are close to the N/A version too which are also avaliable through ACL. The N/A ones are a fraction thicker on the top two compression rings and quite alot thicker in the oil ring seperator. What you do to use these rings, which are readily avaliable, is get the top two ring groves machined out, its only a fraction, and then use your existing oil ring seperator as they dont wear out, they are only a spacer. The oil rings are the same thickness and go straight in place of the old ones.
So, if the bores are still in good condition which they normally are (ive never pulled down an ER which hasnt still got factory hone marks still in it) and your pistons are still ok, then for a relatively small amount of dollars, you can have your City Turbo rebuilt!
