Technical Manifold heat riser/sealant question

Hi all,
So the heat riser on my 51 Plymouth Belvedere needs some work and I have a question about a sealant needed when putting it back together. In the manual it doesn't go into great detail of course, but it does mention that when removing the manifold I first have to drain the coolant as two of the bolts on the manifold go through the water passages.

I've got all the new gaskets needed and a rebuild kit (gaskets, spring, etc) for the heat riser and plan to take this on soon, but first I'm curious what sealant I should use on the bolts that go into the water passages when putting everything back together. Considering RTV Sealant, but just double checking with those who have done this more than me. Any advice appreciated!

 

Thanks! Just read elsewhere about RTV Sealant, but have not used before.

 

3H Permatex

 

Thanks!