I've also considered Clem headset replacement! Mostly to move the rinko style cups onto another project frame which may have more rinko-like adaptability and use a new spare Tange headset on the Clem. Unfortunately, this is unlikely to occur anytime soon with my general lack of spare time... even during quarantine I'm finding I have little extra time for projects. It's weird how this has impacted so many people so differently. I'm extremely fortunate to still be working but work is keeping me busier than ever without even leaving home and it's been a struggle to maintain work/life balance lately. I need some cabin fever projects but can't seem to get to them. This reply itself is a much needed distraction from both work and home.
I've only done a few DIY headset installs and found the threaded rod/nuts/washers press has served me well as long as I go slowly and press one cup at a time... but I eventually added the following tools to my bike toolbox:
Headset cup remover! - after multiple frustrating attempts at DIY cup removals (brass rod, flathead screw driver, etc.) I finally ordered one of these and it's entirely worth it... takes a single whack or two with a mallet per cup and keeps your cups intact - good trick I learned (Sheldon, maybe?) is to use a rag and rubber band around the headtube to catch your cups so they don't fall onto the hard floor and risk damage.
Crown race setter - I went with the Park Tool version which has a few inserts for 1" and 1-1/8"
Crown race puller - forget the model and it's ok but finally got one after struggling with a particular crown race and fork which left little room for any other kind of punch.
All of these were eventually acquired over time along with several other bike specific tools and after finally deciding to undertake relatively simple tasks on my own following some highly unsatisfactory LBS services... not one particular occasion but more of a series of occasions at multiple local shops which just left me with a bitter taste and lack of confidence with levels of service and communication and/or a general lack of interest in some of my particular projects which I think further promoted the poor attention to details and lack of quality service and communication. It's funny, but after a few particular botched jobs or non-existent communication I later found myself testing out different shops in the area with small individual services to vet them for potentially bigger jobs. Several failed at even communicating their completion of a job which I found even more frustrating and they lost out on more business.
If you have any inclination for future headset replacements or have run into a situation where it has stalled potential projects I'd strongly encourage you to consider adding a few of the basic headset tools to your box. It's entirely worth it considering the time it saves if/when you are able to do the rest of the build yourself.
If not and this is likely a one time job and you have a good LBS then I'd recommend letting the LBS do it rather than potentially damage your headset during a botched removal like I have.
Best wishes and good luck!
Brian Cole
Lawrence NJ