Welcome new member. You will find a wealth of information and lots of helpful people with a huge knowledge base here. There are no dumb questions here, only stupid answers!
This website is the most active in the RVing community. Use the search function before posting common questions. The Eisenhower Tunnel and I70 are talked about extensively on the site.
Some of us have driven I70 and the Tunnel for years. It is an Interstate Highway. A gazillion trucks and RVs do it every year. There is a major construction project east of Idaho Springs. It can be ugly at times. You should have no issues. Keep down geared on the climb to stay in your torque peak. It is a long grind. Sit back and relax. There is a long steep descent on the west side. Be careful to keep your speed in check.
FYI: You might want to check cotrip.org (Colorado Dept of Trans) for alerts on I70 and the Idaho Springs construction.
There is a slow steep but much shorter climb up Freemont and a very, very short and steep descent. It is clear sailing to Salida and US50. When you come south out of downtown Ledville be sure to pay attention to the 35mph speed. They patrol it heavily.
You didn't say which way you were going on 50. North over Monarch Pass is a bit steep with passing lanes. Sit back and enjoy. South to Canyon City is a bit twisty but very scenic. Pay attention to slower speed limits in some of the small "towns."