Vacuum Problem

I'm brand new a doing my own repair, so please bear with me.
I noticed that my '92 Buick Lesabres vacuum line connector hoses were seriously cracked, so I decided that this should be an easy first repair job. These rubber hoses were connecting the manifold vacuum tee (little box that sits on top of the intake manifold) to some more substantial hard vacuum lines and the fuel pressure regulator.
I went to autozone and the clerk got me a length of hose that looked of similar diameter. This hose is near impossible to get on the vacuum tee. I eventually had to remove the vacuum tee and after much struggling and twisting I got the hoses on the tee but now that one end is fixed to the tee I can't twist and turn it onto the vacuum line ends. Is it really supposed to be so difficult to get these hoses into place? Or is this the wrong size hose? What size hose should go there (It's a little hard to tell from the old ones because they are in such bad shape)?
Furthermore when I removed that vacuum tee, some sort of gasket fell off of it and crumbled. I tried to look around online, but I can't find this gasket online (probably because I don't know the real name of the vacuum tee). Does anyone know the real name of that vacuum tee that sits on top of the intake manifold and where to find a replacement gasket for it?


Thanks in advance for any advice.

It is usually called a vacuum distribution manifold or junction, you may have to make the gasket, as far as the hoses measure the size of the fittings on the tee.

If the hose is the right size and is just hard to put on, a little heat applied to the hose via a lightbulb, butane lighter, etc. can make it much easier to slip it onto the fitting. Just be careful not to burn a hole in the hose.

I went to autozone and the clerk got me a length of hose that looked of similar diameter. Is it really supposed to be so difficult to get these hoses into place? Or is this the wrong size hose?You should not have to heat, or otherwise force the hose on the fittings. A good snug fit is all that is necessary. Take a sample of the old hose with you next time. BTW, if you use a small amount of lube on the fitting prior to installing, it would help!

A common mistake when replacing vacuum hoses is to look only at the hose's outside diameter, which is not always proportional to the inside diameter. You need hose with the correct size inside diameter. Probably would be best to buy more hose that fits better.