Bought GMC Pauls gasket kit for HVAC, do I need extra sealer?

[Rob68c10]

I just got my HVAC rebuild kit from GMC Pauls. It comes with gaskets to seal everything. When it comes to sealing the box to the firewall, should I just use the gasket? Or do I need to add something extra to it like an RTV?

I tried emailing them but I haven't gotten a response.

Thanks

[GMCPaul]

In answer to your question no sealant required. I may have located your order by searching for Maryland orders for A/C heater gasket set and I'm also going to be emailing you now as we show no emails in any of email accounts from you on the email address used on the order I'm referring to.
Paul Jr @ GMCPauls

[Rob68c10]

Just wanted to let anyone know who finds this thread that GMC Paul did contact me and get this resolved. This was in no way their fault. In fact something went wrong with my email and it was not delivered.

I give their customer service an excellent rating!