The idea that Eric (why not Dylan?) was influenced by Tim McVeigh seems to be solely due to his "America, love it or leave it" rant and his wish that he would get the high score for casualties in an attack, at the time held by McVeigh.
Other than that, I don't think there is any influence, just like the Anarchists Cookbook being a source of great influence for them, it's mostly a myth.
I suspect Duke Nukem level 2 was much more of an influence, and is what Eric is talking about when he talks about being into demolition, or parking garages exploding and flames licking up buildings. The bombs were pipes bombs attached to propane tanks, straight out of Duke Nukem 3D. All their weapons were from vidya.
Go to 2:45 here,
[You must be registered and logged in to see this link.]I think that was in his mind a lot more than OKC. In the quote "It's gonna be like the LA Riots, Oklahoma bombing, WW2, Vietnam, Duke, and DOOM" the two video games at the end are the most relevant. The rest is all video games, I'm convinced. LA Riots = Duke Nukem 3D, it's set in LA with mutated LAPD pig cops (it says LARD instead). What I just showed you for Oklahoma bombing.
Wolfenstein 3d for WW2. Blood for Vietnam (where they got the idea for napalm).
And just no about Eric looking like him. Eric looked a lot DOOMGUY. That's who he was thinking of when he got his haircut or similar. That's why he got a nose bleed. His usernames were rebdoomer not rebokcer.
And that idea that Tim was bullied in school - rather than proving a parallel to Columbine - seems to show how easily every crime is chalked up to abuse and mental health regardless of the evidence, Columbine included.
They wanted to play video games IRL, kill cops for the van arrest, and have followers who wanted to do the same, not to extract revenge for Waco and Ruby Ridge.
Further, it seems to me the division of labor was Eric was gun man, and Dylan was bomb tech. The guns were from DOOM, Eric's favorite game. The bombs were from Duke Nukem 3D, I suspect Dylan's favorite. His triple barred cross he drew a lot, and wore on his ear, and said symbolized "the everlasting contrast" and "the everything" i. e. both good and evil, is from Duke Nukem level 3. Dylan was doing "missions" and so it seems to me making pipe bombs with Zach before Eric was. Duke was blond and wanted girls. Given that, extra silly to say Eric was McVeigh guy rather than Dylan. But neither were.