A few questions about my lower unit

So my 1986 cobra trim sending unit isn’t functioning and I’d like to replace it. I’m not certain the condition of the bellows, gimbal etc since I just purchased the boat in July. I did take it out twice and everything seemed to function well on those trips and I took on no water. Anyway, if I need to replace the sending unit and must remove the outdrive are there special tools required to replace gimbal bearing etc and or special skills needed. I’m comfortable doing any mechanical job but I want to know if there’s anything highly technical required. Thanks

To do gimbal bearing you need a slide hammer to pull it and an alignment tool to check motor alignment

I have done it with out the slide hammer with a 1/2” threaded rod a couple fender washers and a piece 2x4 you can make a puller that is a little bit hinky to use but works