Jon Parkin, Damien Johnson and Barry Nicholson are among the eye-catching additions already brought in as the Cod Army prepare for their Football League bow next month.
Mellon told Fleetwood Weekly News: "They are two long-term targets who will be the final pieces of the jigsaw. We have reached agreement with them and hope to have the contracts finalised by Friday."
Mellon rang the changes during Wednesday's opening friendly against Gateshead, running the rule over 25 players during the 1-0 defeat - including several trialists.
"It was essentially a training game but a lot of players got a 45-minute workout," he added. "It was a useful guide to where we are fitness-wise.
"The new players did what we expected of them and there were some promising signs."