Striker Heskey, 34, is poised to lead the attack at Villa Park if captain Gabriel Agbonlahor fails to recover from a shoulder problem. Cuellar is required to fill the gap at the back left by the absence of central defender James Collins through a groin problem.
McLeish said: "It depends on Gabby, but Emile would come right into the thinking for tonight. He's admired by all his team-mates... It's the same scenario with someone like Carlos. The thing about guys like that is that they have total commitment to any particular task that they have to undertake."
On Heskey, he added: "His team-mates love him, and love him playing in the team, because they know he's going to work his socks off for the cause and he's going to create chances for them.
"He's capable of scoring as well when he's playing in his favourite position of centre forward. I think Michael Owen said he was the best partner he ever played with."
Of the pair, Mcleish added: "Those two are fine examples of that, two guys who will go through brick walls for you and for the club - regardless of what happens next."
McLeish also confirmed Cuellar was the "outstanding candidate" to skipper the side if Agbonlahor is ruled out.
The Scot has challenged Villa to improve their home record and show a ruthless streak. They have recorded just four victories in front of their own supporters this season and lie only five points above the bottom three.
McLeish said: "Our record at home is rotten. It's not something we are proud of. It's something we can't do anything about now but we've got to do something about the next game. We've got to go all out to win it.
"The stakes of the Premier League are enormous. This next game is huge for us and Bolton and we've got to go for it and the players are totally committed and ready for the cause. We've lost sucker equalisers in the last few minutes. These points become vital when you get to this stage of the season."
Source: PA
Source: PA