Starter issues

I have 2000 suburban, recenttly I drive in a lot of rain, and since then my shift inicator, is inaccurate, it shows 3rd, but will not light up ant nuetral, drive or reverse, and as of yesterday my starter has been attepting to engage while sitting in pary, with the car running, I replaced the starter, and once I crnk it it is fine but after driving, and putting the car in park. The new starter is doing the same. Thing. My next move is to replace the shift linkage solenoid at the tranny. Any advice