The Maryland Jockey Club has unveiled a $420 million plan for tearing down and rebuilding its tracks and training facilities if the General Assembly adopts Gov. Robert L. Ehrlich Jr.'s proposal for slot machines at racetracks.Construction plans call for a feverish rebuilding of all aspects of Pimlico and Laurel Park. The grandstands and clubhouses would be reconstructed so they could accommodate slot machines. The racing surfaces and stable areas would be rebuilt. The training center at Bowie would be bulldozed and a new one constructed, or a new training center would be built elsewhere."The plan is to do everything first-class, including the barns," said Lou Raffetto Jr., MJC chief operating officer. "If we get slots, the amount of work that needs to be done is incredible. It will take an effort of gigantic proportions. But there's no thinking it's not going to happen. Everybody is looking forward to the end result -- two new racetracks and a training center we can be proud of."Gov. Ehrlich has proposed 3,500 slot machines each at Pimlico, Laurel Park and Rosecroft Raceway, a harness track in southern Maryland, and another 1,000 at a track under construction in western Maryland. Under the governor's revised plan released Wednesday, track owners would receive 46 percent of slots proceeds. However, the fate of slots legislation in the General Assembly is uncertain, as a vocal opposition has emerged.Raffetto said construction planning began in November - after Ehrlich's election and the closing of the deal between the MJC and Magna Entertainment Corp. Magna became majority owner of the MJC in a $117.5 million deal finalized Nov. 27.Raffetto said the MJC would borrow $500 million and repay it with profits from slots. Of that $500 million, $80 million would go for license fees to the state -- $40 million each for Pimlico and Laurel Park. The remaining $420 million would go for construction - about $200 million each at Pimlico and Laurel Park, and about $20 million at Bowie or a new training center.The construction timetable would be speeded up so that slot machines could be operational as soon as possible, Raffetto said. The goal would be to complete all work within 24 months."A lot of this is ambitious," Raffetto said. "And everything's a huge puzzle. How do you redo a track and continue training and racing? Given the proper manpower and a lot of a money, we're told we can get the job done."After racing shifts from Laurel to Pimlico at the end of March, the MJC would begin tearing down Laurel Park in April - if slots are approved, Raffetto said. A new clubhouse and grandstand would be built, combining slots and horse betting, and the dirt and grass racing surfaces would be rebuilt. Also, a new stable would be constructed - possibly with a training track.Then, Raffetto said, as soon as Pimlico ends its meet in June, work would begin there. The end result would be a new grandstand and clubhouse with slots and betting areas, new dirt and turf tracks, and barns with 250 stalls for horses shipping in to race and for Preakness week. No more year-round stabling would take place at Pimlico, he said.Instead, the stable areas would be enlarged at Laurel and at Bowie or a new center. The decision on whether to rebuild Bowie has not been made, Raffetto said. Work would be done in phases so that some areas of each track would remain open for betting while others were closed for construction. Raffetto said plans call for work so swift at Pimlico that the Preakness could be run there in 2004.